Retrofitting for Sustainable Building Performance: A Scientometric–PESTEL Analysis and Critical Content Review

As climate change mitigation intensifies, retrofitting existing buildings has emerged as a critical and cost-effective strategy to improve energy performance, resilience, and sustainability. This systematic literature review (SLR) analysed 97 peer-reviewed articles published between 2015 and 2025, retrieved from the Scopus database using a title-based search strategy combining keywords related to building performance and retrofit actions. A five-stage screening process was employed to refine results based on publication type, discipline relevance, and research alignment. VOSviewer was used for scientometric mapping, complemented by descriptive and content analyses, to identify six thematic clusters: envelope optimisation, energy economics, environmental quality, system efficiency, passive retrofitting, and digital/data-driven planning. The review also applies a PESTEL framework to evaluate retrofit benefits across political, economic, social, technological, environmental, and legal dimensions. Finally, seven future research directions are proposed, including digital twin (DT) integration, artificial intelligence (AI) adoption, circular economy (CE) principles, stakeholder engagement, and climate-resilient design. By consolidating fragmented research, this study provides actionable insights for scholars, practitioners, and policymakers, establishing building retrofitting as a strategic pathway toward sustainable and climate-responsive urban development.